1. Field of the Invention
The present invention relates to a spindrier for drying substrates such as semiconductor wafers while removing solution or solution drops from them.
2. Description of the Related Art
Semiconductor devices such as super LSIs have been more and more highly integrated and their circuit patterns have been micro-structured to the order of submicrons. In addition, the diameter of wafers has been made large and larger, say, to 8 inches and 12 inches. Even if a quite little amount of particles which could be neglected should adhere to the surface of each wafer, therefore, the productivity of wafers will be lowered to a great extent. To solve this, the semiconductor wafers are immersed in acid and alkali solutions in cleaning vessels of the automatic cleaning system. Their surfaces can be thus made clean.
According to the automatic cleaning system, the wafers are washed by chemical solution and then water-washed and dried. A spindrier is used in the drying chamber of the automatic cleaning system in order to made the manufacturing efficiency of wafers high. Japanese Patent Disclosure Hei 1-255227 discloses one of these spindriers, however, air or gas is caused to flow perpendicular to the surface of each wafer and its flow is easily drifted in the housing. This makes it difficult to efficiently separate solution or solution drops from the wafers and to efficiently discharge particles and moisture content outside the housing.
Further, gas is likely to stay in the bottom portion and upper corners of the housing in the case of the conventional spindriers. If particles are contained in the gas thus stayed, therefore, they adhere to the wafers and contaminate them when the flow of gas is stopped.
Still further, the interval of each wafer set relative to each side wall of the clamp groove is so narrow as to allow solution to remain in it. This makes it impossible to completely dry the wafers.